The present invention relates to a digital copying machine and an image reader provided with the functions of offline image input and output using a removable storage medium.
Recently, the demand for high speed and multi-functional digital copying machines has arisen, and a digital copying machine provided with a facsimile function, a printer function, etc. in addition to a copy function has been developed. A conventional digital copying machine will be described below, referring to the figures. FIG. 13 is a block diagram which shows a flow chart for an image signal of a conventional digital copying machine.
As shown in FIG. 13, an image sensor 71 scans an original to convert reflected light from the original to an electric signal. An analog image signal from image sensor 71 is then converted to a digital image signal by an analog-to-digital (A/D) converter 72. The converted digital image signal is subjected to image processing such as edge enhancement, trimming, and halftone processing, and edit processing in an image processor 73. An image signal given by image processor 73 is buffered in a buffer memory 74 for speed control to be given to a laser driver 78. Laser driver 78 drives a semiconductor laser 79 to form an electrostatic latent image by laser beams given by semiconductor laser 79.
The digital copying machine further comprises a central processing unit (CPU) 85, a local area network (LAN) controller 80, a page memory 84, a parallel interface (I/F) 81, a communication control unit (CCU) 82, and a compressor/expander 86 which are mutually connected by a CPU bus 83.
CPU 85 comprises a random access memory (RAM) and a read only memory (ROM) and controls the entire digital copying machine. Page memory 84 has capacity that can store at least one page of image data and is connected to buffer memory 74. Image data stored in page memory 84 is given to laser driver 78 through buffer memory 74 to be printed on paper.
LAN controller 80 communicates with an external equipment through a local area network (LAN). When the digital copying machine is used as a remote printer, an external equipment such as a computer transmits a print control command and image data to the digital copying machine through the LAN. CPU 85 stores the image data received through the LAN into the page memory according to the received print control command.
Using parallel I/F 81, the digital copying machine and an external equipment can be connected one to one. When the digital copying machine is used as a printer for the external equipment, the external equipment transmits a print control command and image data to the digital copying machine through the parallel I/F of the digital copying machine. When the image scanner function of the digital copying machine is used by the external equipment, the external equipment transmits an image read control command to the digital copying machine through parallel I/F 81, and read image data is transmitted to the external equipment from the digital copying machine.
CCU 82 communicates with an external facsimile through a public network using a modem 87. Image data received by the facsimile is expanded in compressor/expander 86, transferred to page memory 84, and printed. Also, image data read for facsimile transmission is stored in page memory 84, compressed in compressor/expander 86, and transmitted to the external facsimile through CCU 82 and modem 87.
Generally, a high-speed digital plain paper copier (PPC) which is capable of copying more than tens of sheets per minute is located in a common space such as a copy room or a hallway. When copying a document which is prepared by a personal computer, etc. in plural copies, a user has to print the original by a nearby printer, take the original to a place where a digital copying machine is located, and then copy the original in plural copies using a sorter, etc. of the digital copying machine. Especially, when a personal computer used by a user is not connected through a LAN, the remote print function of the digital copying machine can not be used, so that copying must be done as mentioned above. In this case, an original image is once printed on paper before copying it, and therefore the image is inevitably degraded.
When a personal computer used by a user is connected to the digital copying machine through a LAN, the user can use the remote print function of the digital copying machine. Therefore, the user can directly utilize a function such as a sorter of the digital copying machine from his personal computer. However, when copying by using the remote print function of the digital copying machine, the user has to go to a distant place where the digital copying machine is located to take printed paper. Also, when copying in large amount using the remote print function, problems such as using up paper and paper jam are likely to occur. To solve these troubles, the user also has to go to the place where the digital copying machine is located. Thus, the utility value of the remote (online) print function in a high-speed digital copying machine is not very high.
When using the image scanner function of the digital copying machine from a user""s personal computer online by using the parallel I/F and the LAN, similar problems arise. That is, the user has to go to a distant place where the digital copying machine is located to set an original in the image scanner part of the digital copying machine. Therefore, when the digital copying machine and the user""s computer are located a distance apart, it is not useful to use the image scanner function of the digital copying machine online.
Next, a conventional image reader will be described. FIG. 21 is a block diagram showing a flow chart for an image signal of a conventional image reader. An image sensor 171 scans an original to convert reflected light from the original to an electric signal. An analog image signal given by image sensor 171 is converted to a digital image signal by an A/D converter 172, and given to an image processor 173. Image processor 173 performs image processing such as edge enhancement, trimming, halftone processing, pixel density conversion, and gradation level conversion as well as edit processing on the digital image signal. Image data given by image processor 173 is stored in a buffer memory 174.
For controlling the entire image reader, a CPU 185 comprising a RAM and a ROM is provided. CPU 185, image processor 173, buffer memory 174, a DMA (direct memory access) controller 180, and a small computer system interface (SCSI) controller 181 are mutually connected through a CPU bus 183.
DMA controller 180 transfers image data stored in buffer memory 174 to SCSI controller 181 directly. An external equipment such as a computer transmits a control command for the image reader to the image reader through the SCSI controller and receives image data from the image reader. CPU 185 sets the degree of edge enhancement, the gradation level of image data, read density, etc. according to the image read control command.
Such an image reader is connected to an external equipment such as a personal computer one to one using an interface such as a SCSI. Therefore, the image reader is used exclusively by the user of the connected personal computer. When another user uses the image reader, the user has to use the personal computer connected to the image reader or connect the image reader to his personal computer.
The present invention provides a digital copying machine and an image reader provided with an interface for offline image input and output using a removable storage medium.
According to a first aspect of a digital copying machine of the present invention, the digital copying machine comprises means for reading an original image to reproduce the image data of the original image (e.g. an image scanner), means for printing an image according to given image data (e.g. a laser printer), means for accessing a removable storage medium (e.g. a reader/writer of a memory card), and means for controlling the printing means according to output control data stored in the storage medium so that the printing means can print an image according to image data stored in the storage medium.
Preferably, the digital copying machine further comprises a sorter for sorting printed paper, a finisher for stapling printed paper, and means for controlling the sorter or the finisher according to output control data stored in the storage medium.
Preferably, the digital copying machine further comprises means for storing information of the functions of the printing means and the finisher into the storage medium so that the information can be used by an external equipment such as a computer for generating the output control data.
Preferably, in order to store as much information as possible into the storage medium having limited storage capacity, the image data is compressed by encoding, and the digital copying machine further comprises means for expanding the compressed image data. Preferably, the digital copying machine further comprises means for erasing output control data and image data stored in the storage medium after printing the image data.
According to the digital copying machine of the present invention as mentioned above, by storing the image data of a document, etc. prepared by an external equipment such as a personal computer and output control data into the removable storage medium, and installing the storage medium in the digital copying machine of the present invention, the digital copying machine prints image data read out from the storage medium offline in a desired output form. As a result, a user can directly copy a document in copies of a predetermined number using the digital copying machine of the present invention, without the need for copying an original which is previously printed by a nearby printer. In this case, the image quality of a copy is advantageously not degraded.
Also, by controlling the sorter or finisher of the digital copying machine according to output control data stored in the storage medium, a user can specify the number of copies, a sorting or stapling method, etc. when a document, etc. is prepared by an external computer.
Furthermore, by previously storing (downloading) information of functions provided in the the digital copying machine, for example, the printing means and the sorter or finisher, a user can effectively use all the functions of the digital copying machine.
According to a second aspect of a digital copying machine of the present invention, the digital copying machine comprises means for reading an original image to reproduce the image data of the original image, means for printing an image according to given image data, means for accessing a removable storage medium, and means for controlling the image reading means according to read control data stored in the storage medium so that the image reading means can read an original image so as to produce the image data of the original image to be stored in the storage medium.
In the above aspect, preferably, in order to generate the read control data using an external equipment such as a computer, the digital copying machine further comprises means for storing information of the function of the image reading means into the storage medium. Preferably, the digital copying machine further comprises means for compressing image data given by the image reading means.
According to the digital copying machine of the present invention as mentioned above, offline image input using an image scanner function is readily implemented. That is, read control data obtained by using the image scanner, for example, a read gradation level, a read size, an image compressing method, the degree of edge enhancement, contrast, read density, and an image data file name are stored in a removable storage medium using software executed in an external computer. Then, the storage medium is installed in the digital copying machine, an original to be read is set in the digital copying machine, an original image is read according to the read control data stored in the storage medium, and image data is stored in the storage medium. A user removes the storage medium from the digital copying machine and installs it in a personal computer, for example, and desired image data can be read out from the storage medium to the personal computer.
According to a first aspect of an image reader of the present invention, the image reader comprises an image sensor for converting optical information from an original image to an electric signal, an A/D converter for converting the electric signal given by the image sensor to a digital image signal, an image processor for processing the digital image signal to produce image data, means for accessing a removable storage medium, and means for controlling the image processor according to read control data stored in the storage medium so that the image processor can produce the image data to be stored in the storage medium.
According to a second aspect of an image reader of the present invention, the image reader comprises an image sensor for converting optical information from an original image to an electric signal, an A/D converter for converting the electric signal given by the image sensor to a digital image signal, an image processor for processing the digital image signal to produce image data, an interface for transmitting the image data to an external equipment, means for accessing a removable storage medium, and means for selecting either transmitting the image data to the external equipment by the interface or storing the image data into the storage medium by the accessing means.
According to the image reader of the present invention as mentioned above, a user stores read control data, for example, a read gradation level, a read size, an image compressing method, the degree of edge enhancement, contrast, read density, and an image data file name into a removable storage medium using software executed in an external computer. Then, the storage medium is installed in the image reader of the present invention, and an original to be read is set in the image reader. The image reader of the present invention reads an original image according to the read control data stored in the storage medium, and read image data is stored into the storage medium. Thus, an offline image input function is implemented. A user removes the storage medium from the image reader of the present invention and installs it in a personal computer, etc., and desired image data can be read out from the storage medium to the personal computer, etc.
By providing the image reader with the offline image input function as mentioned above, in addition to a conventional one-to-one interface with an external equipment, the image reader can be connected one to one to a personal computer of a user who uses the image reader most frequently, and other users can use the image reader using the offline image input function without changing the connection.
Also, the image reader of the present invention can output read image data offline in a different read form for each user into the storage medium. Furthermore, a user can readily generate read control data using the user interface of a personal computer, for example. Even if a computer is not connected to the image reader as in the case of a portable note-type computer, an original image can be readily read offline using a memory card, etc.
Furthermore, the image reader of the present invention can download information of the image read function of the image reader to the storage medium, so that a user can readily utilize all the functions of the image reader.